/
IMG_bmp.c
845 lines (775 loc) · 20.7 KB
1
/*
2
SDL_image: An example image loading library for use with SDL
3
Copyright (C) 1997-2009 Sam Lantinga
4
5
This library is free software; you can redistribute it and/or
6
modify it under the terms of the GNU Lesser General Public
7
License as published by the Free Software Foundation; either
8
version 2.1 of the License, or (at your option) any later version.
9
10
11
12
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13
Lesser General Public License for more details.
14
15
16
17
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18
19
Sam Lantinga
20
slouken@libsdl.org
21
22
*/
23
24
#if !defined(__APPLE__) || defined(SDL_IMAGE_USE_COMMON_BACKEND)
25
/* This is a BMP image file loading framework */
26
27
/* ICO/CUR file support is here as well since it uses similar internal
* representation */
28
29
30
31
32
33
34
35
36
37
38
#include <stdio.h>
#include <string.h>
#include "SDL_image.h"
#ifdef LOAD_BMP
/* See if an image is contained in a data source */
int IMG_isBMP(SDL_RWops *src)
{
39
int start;
40
41
42
int is_BMP;
char magic[2];
43
44
if ( !src )
return 0;
45
start = SDL_RWtell(src);
46
is_BMP = 0;
47
if ( SDL_RWread(src, magic, sizeof(magic), 1) ) {
48
49
50
51
if ( strncmp(magic, "BM", 2) == 0 ) {
is_BMP = 1;
}
}
52
SDL_RWseek(src, start, RW_SEEK_SET);
53
54
55
return(is_BMP);
}
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
static int IMG_isICOCUR(SDL_RWops *src, int type)
{
int start;
int is_ICOCUR;
/* The Win32 ICO file header (14 bytes) */
Uint16 bfReserved;
Uint16 bfType;
Uint16 bfCount;
if ( !src )
return 0;
start = SDL_RWtell(src);
is_ICOCUR = 0;
bfReserved = SDL_ReadLE16(src);
bfType = SDL_ReadLE16(src);
bfCount = SDL_ReadLE16(src);
if ((bfReserved == 0) && (bfType == type) && (bfCount != 0))
is_ICOCUR = 1;
75
SDL_RWseek(src, start, RW_SEEK_SET);
76
77
78
79
80
81
82
83
84
85
86
87
88
89
return (is_ICOCUR);
}
int IMG_isICO(SDL_RWops *src)
{
return IMG_isICOCUR(src, 1);
}
int IMG_isCUR(SDL_RWops *src)
{
return IMG_isICOCUR(src, 2);
}
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
#include "SDL_error.h"
#include "SDL_video.h"
#include "SDL_endian.h"
/* Compression encodings for BMP files */
#ifndef BI_RGB
#define BI_RGB 0
#define BI_RLE8 1
#define BI_RLE4 2
#define BI_BITFIELDS 3
#endif
static int readRlePixels(SDL_Surface * surface, SDL_RWops * src, int isRle8)
{
/*
| Sets the surface pixels from src. A bmp image is upside down.
*/
int pitch = surface->pitch;
int height = surface->h;
109
110
111
Uint8 *start = (Uint8 *)surface->pixels;
Uint8 *end = start + (height*pitch);
Uint8 *bits = end-pitch, *spot;
112
113
114
115
int ofs = 0;
Uint8 ch;
Uint8 needsPad;
116
117
#define COPY_PIXEL(x) spot = &bits[ofs++]; if(spot >= start && spot < end) *spot = (x)
118
119
120
121
122
123
124
125
126
127
128
for (;;) {
if ( !SDL_RWread(src, &ch, 1, 1) ) return 1;
/*
| encoded mode starts with a run length, and then a byte
| with two colour indexes to alternate between for the run
*/
if ( ch ) {
Uint8 pixel;
if ( !SDL_RWread(src, &pixel, 1, 1) ) return 1;
if ( isRle8 ) { /* 256-color bitmap, compressed */
do {
129
COPY_PIXEL(pixel);
130
} while (--ch);
131
} else { /* 16-color bitmap, compressed */
132
133
134
Uint8 pixel0 = pixel >> 4;
Uint8 pixel1 = pixel & 0x0F;
for (;;) {
135
COPY_PIXEL(pixel0); /* even count, high nibble */
136
if (!--ch) break;
137
COPY_PIXEL(pixel1); /* odd count, low nibble */
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
if (!--ch) break;
}
}
} else {
/*
| A leading zero is an escape; it may signal the end of the bitmap,
| a cursor move, or some absolute data.
| zero tag may be absolute mode or an escape
*/
if ( !SDL_RWread(src, &ch, 1, 1) ) return 1;
switch (ch) {
case 0: /* end of line */
ofs = 0;
bits -= pitch; /* go to previous */
break;
case 1: /* end of bitmap */
return 0; /* success! */
case 2: /* delta */
if ( !SDL_RWread(src, &ch, 1, 1) ) return 1;
ofs += ch;
if ( !SDL_RWread(src, &ch, 1, 1) ) return 1;
bits -= (ch * pitch);
break;
default: /* no compression */
if (isRle8) {
needsPad = ( ch & 1 );
do {
165
166
167
Uint8 pixel;
if ( !SDL_RWread(src, &pixel, 1, 1) ) return 1;
COPY_PIXEL(pixel);
168
169
170
171
172
173
} while (--ch);
} else {
needsPad = ( ((ch+1)>>1) & 1 ); /* (ch+1)>>1: bytes size */
for (;;) {
Uint8 pixel;
if ( !SDL_RWread(src, &pixel, 1, 1) ) return 1;
174
COPY_PIXEL(pixel >> 4);
175
if (!--ch) break;
176
COPY_PIXEL(pixel & 0x0F);
177
178
179
180
181
182
183
184
185
186
187
188
189
if (!--ch) break;
}
}
/* pad at even boundary */
if ( needsPad && !SDL_RWread(src, &ch, 1, 1) ) return 1;
break;
}
}
}
}
static SDL_Surface *LoadBMP_RW (SDL_RWops *src, int freesrc)
{
190
SDL_bool was_error;
191
192
193
194
195
196
197
long fp_offset;
int bmpPitch;
int i, pad;
SDL_Surface *surface;
Uint32 Rmask;
Uint32 Gmask;
Uint32 Bmask;
198
Uint32 Amask;
199
200
SDL_Palette *palette;
Uint8 *bits;
201
202
Uint8 *top, *end;
SDL_bool topDown;
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
int ExpandBMP;
/* The Win32 BMP file header (14 bytes) */
char magic[2];
Uint32 bfSize;
Uint16 bfReserved1;
Uint16 bfReserved2;
Uint32 bfOffBits;
/* The Win32 BITMAPINFOHEADER struct (40 bytes) */
Uint32 biSize;
Sint32 biWidth;
Sint32 biHeight;
Uint16 biPlanes;
Uint16 biBitCount;
Uint32 biCompression;
Uint32 biSizeImage;
Sint32 biXPelsPerMeter;
Sint32 biYPelsPerMeter;
Uint32 biClrUsed;
Uint32 biClrImportant;
/* Make sure we are passed a valid data source */
surface = NULL;
227
was_error = SDL_FALSE;
228
if ( src == NULL ) {
229
was_error = SDL_TRUE;
230
231
232
233
234
235
236
237
goto done;
}
/* Read in the BMP file header */
fp_offset = SDL_RWtell(src);
SDL_ClearError();
if ( SDL_RWread(src, magic, 1, 2) != 2 ) {
SDL_Error(SDL_EFREAD);
238
was_error = SDL_TRUE;
239
240
241
242
goto done;
}
if ( strncmp(magic, "BM", 2) != 0 ) {
SDL_SetError("File is not a Windows BMP file");
243
was_error = SDL_TRUE;
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
goto done;
}
bfSize = SDL_ReadLE32(src);
bfReserved1 = SDL_ReadLE16(src);
bfReserved2 = SDL_ReadLE16(src);
bfOffBits = SDL_ReadLE32(src);
/* Read the Win32 BITMAPINFOHEADER */
biSize = SDL_ReadLE32(src);
if ( biSize == 12 ) {
biWidth = (Uint32)SDL_ReadLE16(src);
biHeight = (Uint32)SDL_ReadLE16(src);
biPlanes = SDL_ReadLE16(src);
biBitCount = SDL_ReadLE16(src);
biCompression = BI_RGB;
biSizeImage = 0;
biXPelsPerMeter = 0;
biYPelsPerMeter = 0;
biClrUsed = 0;
biClrImportant = 0;
} else {
biWidth = SDL_ReadLE32(src);
biHeight = SDL_ReadLE32(src);
biPlanes = SDL_ReadLE16(src);
biBitCount = SDL_ReadLE16(src);
biCompression = SDL_ReadLE32(src);
biSizeImage = SDL_ReadLE32(src);
biXPelsPerMeter = SDL_ReadLE32(src);
biYPelsPerMeter = SDL_ReadLE32(src);
biClrUsed = SDL_ReadLE32(src);
biClrImportant = SDL_ReadLE32(src);
}
276
277
278
279
280
281
if (biHeight < 0) {
topDown = SDL_TRUE;
biHeight = -biHeight;
} else {
topDown = SDL_FALSE;
}
282
283
284
/* Check for read error */
if ( strcmp(SDL_GetError(), "") != 0 ) {
285
was_error = SDL_TRUE;
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
goto done;
}
/* Expand 1 and 4 bit bitmaps to 8 bits per pixel */
switch (biBitCount) {
case 1:
case 4:
ExpandBMP = biBitCount;
biBitCount = 8;
break;
default:
ExpandBMP = 0;
break;
}
/* RLE4 and RLE8 BMP compression is supported */
302
Rmask = Gmask = Bmask = Amask = 0;
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
switch (biCompression) {
case BI_RGB:
/* If there are no masks, use the defaults */
if ( bfOffBits == (14+biSize) ) {
/* Default values for the BMP format */
switch (biBitCount) {
case 15:
case 16:
Rmask = 0x7C00;
Gmask = 0x03E0;
Bmask = 0x001F;
break;
case 24:
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
Rmask = 0x000000FF;
Gmask = 0x0000FF00;
Bmask = 0x00FF0000;
320
321
322
323
#else
Rmask = 0x00FF0000;
Gmask = 0x0000FF00;
Bmask = 0x000000FF;
324
#endif
325
break;
326
case 32:
327
Amask = 0xFF000000;
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
Rmask = 0x00FF0000;
Gmask = 0x0000FF00;
Bmask = 0x000000FF;
break;
default:
break;
}
break;
}
/* Fall through -- read the RGB masks */
default:
switch (biBitCount) {
case 15:
case 16:
case 32:
Rmask = SDL_ReadLE32(src);
Gmask = SDL_ReadLE32(src);
Bmask = SDL_ReadLE32(src);
347
Amask = SDL_ReadLE32(src);
348
349
350
351
352
353
354
355
356
break;
default:
break;
}
break;
}
/* Create a compatible surface, note that the colors are RGB ordered */
surface = SDL_CreateRGBSurface(SDL_SWSURFACE,
357
biWidth, biHeight, biBitCount, Rmask, Gmask, Bmask, Amask);
358
if ( surface == NULL ) {
359
was_error = SDL_TRUE;
360
361
362
363
364
365
goto done;
}
/* Load the palette, if any */
palette = (surface->format)->palette;
if ( palette ) {
366
if ( SDL_RWseek(src, fp_offset+14+biSize, RW_SEEK_SET) < 0 ) {
367
SDL_Error(SDL_EFSEEK);
368
was_error = SDL_TRUE;
369
370
371
goto done;
}
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
/*
| guich: always use 1<<bpp b/c some bitmaps can bring wrong information
| for colorsUsed
*/
/* if ( biClrUsed == 0 ) { */
biClrUsed = 1 << biBitCount;
/* } */
if ( biSize == 12 ) {
for ( i = 0; i < (int)biClrUsed; ++i ) {
SDL_RWread(src, &palette->colors[i].b, 1, 1);
SDL_RWread(src, &palette->colors[i].g, 1, 1);
SDL_RWread(src, &palette->colors[i].r, 1, 1);
palette->colors[i].unused = 0;
}
} else {
for ( i = 0; i < (int)biClrUsed; ++i ) {
SDL_RWread(src, &palette->colors[i].b, 1, 1);
SDL_RWread(src, &palette->colors[i].g, 1, 1);
SDL_RWread(src, &palette->colors[i].r, 1, 1);
SDL_RWread(src, &palette->colors[i].unused, 1, 1);
}
}
palette->ncolors = biClrUsed;
}
/* Read the surface pixels. Note that the bmp image is upside down */
398
if ( SDL_RWseek(src, fp_offset+bfOffBits, RW_SEEK_SET) < 0 ) {
399
SDL_Error(SDL_EFSEEK);
400
was_error = SDL_TRUE;
401
402
403
404
405
406
407
goto done;
}
if ((biCompression == BI_RLE4) || (biCompression == BI_RLE8)) {
was_error = readRlePixels(surface, src, biCompression == BI_RLE8);
if (was_error) SDL_SetError("Error reading from BMP");
goto done;
}
408
409
top = (Uint8 *)surface->pixels;
end = (Uint8 *)surface->pixels+(surface->h*surface->pitch);
410
411
412
413
414
415
416
417
418
419
420
421
422
423
switch (ExpandBMP) {
case 1:
bmpPitch = (biWidth + 7) >> 3;
pad = (((bmpPitch)%4) ? (4-((bmpPitch)%4)) : 0);
break;
case 4:
bmpPitch = (biWidth + 1) >> 1;
pad = (((bmpPitch)%4) ? (4-((bmpPitch)%4)) : 0);
break;
default:
pad = ((surface->pitch%4) ?
(4-(surface->pitch%4)) : 0);
break;
}
424
425
426
427
428
429
if ( topDown ) {
bits = top;
} else {
bits = end - surface->pitch;
}
while ( bits >= top && bits < end ) {
430
431
432
433
434
435
436
437
438
439
switch (ExpandBMP) {
case 1:
case 4: {
Uint8 pixel = 0;
int shift = (8-ExpandBMP);
for ( i=0; i<surface->w; ++i ) {
if ( i%(8/ExpandBMP) == 0 ) {
if ( !SDL_RWread(src, &pixel, 1, 1) ) {
SDL_SetError(
"Error reading from BMP");
440
was_error = SDL_TRUE;
441
442
443
444
445
446
447
448
449
450
451
452
goto done;
}
}
*(bits+i) = (pixel>>shift);
pixel <<= ExpandBMP;
} }
break;
default:
if ( SDL_RWread(src, bits, 1, surface->pitch)
!= surface->pitch ) {
SDL_Error(SDL_EFREAD);
453
was_error = SDL_TRUE;
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
goto done;
}
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
/* Byte-swap the pixels if needed. Note that the 24bpp
case has already been taken care of above. */
switch(biBitCount) {
case 15:
case 16: {
Uint16 *pix = (Uint16 *)bits;
for(i = 0; i < surface->w; i++)
pix[i] = SDL_Swap16(pix[i]);
break;
}
case 32: {
Uint32 *pix = (Uint32 *)bits;
for(i = 0; i < surface->w; i++)
pix[i] = SDL_Swap32(pix[i]);
break;
}
}
#endif
break;
}
/* Skip padding bytes, ugh */
if ( pad ) {
Uint8 padbyte;
for ( i=0; i<pad; ++i ) {
SDL_RWread(src, &padbyte, 1, 1);
}
}
485
486
487
488
489
if ( topDown ) {
bits += surface->pitch;
} else {
bits -= surface->pitch;
}
490
491
492
}
done:
if ( was_error ) {
493
if ( src ) {
494
SDL_RWseek(src, fp_offset, RW_SEEK_SET);
495
}
496
497
498
499
500
501
502
503
504
505
506
if ( surface ) {
SDL_FreeSurface(surface);
}
surface = NULL;
}
if ( freesrc && src ) {
SDL_RWclose(src);
}
return(surface);
}
507
508
509
510
511
512
513
514
515
516
517
518
static Uint8
SDL_Read8(SDL_RWops * src)
{
Uint8 value;
SDL_RWread(src, &value, 1, 1);
return (value);
}
static SDL_Surface *
LoadICOCUR_RW(SDL_RWops * src, int type, int freesrc)
{
519
SDL_bool was_error;
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
long fp_offset;
int bmpPitch;
int i, pad;
SDL_Surface *surface;
Uint32 Rmask;
Uint32 Gmask;
Uint32 Bmask;
Uint8 *bits;
int ExpandBMP;
int maxCol = 0;
int icoOfs = 0;
Uint32 palette[256];
/* The Win32 ICO file header (14 bytes) */
Uint16 bfReserved;
Uint16 bfType;
Uint16 bfCount;
/* The Win32 BITMAPINFOHEADER struct (40 bytes) */
Uint32 biSize;
Sint32 biWidth;
Sint32 biHeight;
Uint16 biPlanes;
Uint16 biBitCount;
Uint32 biCompression;
Uint32 biSizeImage;
Sint32 biXPelsPerMeter;
Sint32 biYPelsPerMeter;
Uint32 biClrUsed;
Uint32 biClrImportant;
/* Make sure we are passed a valid data source */
surface = NULL;
553
was_error = SDL_FALSE;
554
if (src == NULL) {
555
was_error = SDL_TRUE;
556
557
558
559
560
561
562
563
564
565
566
567
goto done;
}
/* Read in the ICO file header */
fp_offset = SDL_RWtell(src);
SDL_ClearError();
bfReserved = SDL_ReadLE16(src);
bfType = SDL_ReadLE16(src);
bfCount = SDL_ReadLE16(src);
if ((bfReserved != 0) || (bfType != type) || (bfCount == 0)) {
SDL_SetError("File is not a Windows %s file", type == 1 ? "ICO" : "CUR");
568
was_error = SDL_TRUE;
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
goto done;
}
/* Read the Win32 Icon Directory */
for (i = 0; i < bfCount; i++) {
/* Icon Directory Entries */
int bWidth = SDL_Read8(src); /* Uint8, but 0 = 256 ! */
int bHeight = SDL_Read8(src); /* Uint8, but 0 = 256 ! */
int bColorCount = SDL_Read8(src); /* Uint8, but 0 = 256 ! */
Uint8 bReserved = SDL_Read8(src);
Uint16 wPlanes = SDL_ReadLE16(src);
Uint16 wBitCount = SDL_ReadLE16(src);
Uint32 dwBytesInRes = SDL_ReadLE32(src);
Uint32 dwImageOffset = SDL_ReadLE32(src);
if (!bWidth)
bWidth = 256;
if (!bHeight)
bHeight = 256;
if (!bColorCount)
bColorCount = 256;
//printf("%dx%d@%d - %08x\n", bWidth, bHeight, bColorCount, dwImageOffset);
if (bColorCount > maxCol) {
maxCol = bColorCount;
icoOfs = dwImageOffset;
//printf("marked\n");
}
}
/* Advance to the DIB Data */
if (SDL_RWseek(src, icoOfs, RW_SEEK_SET) < 0) {
SDL_Error(SDL_EFSEEK);
602
was_error = SDL_TRUE;
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
goto done;
}
/* Read the Win32 BITMAPINFOHEADER */
biSize = SDL_ReadLE32(src);
if (biSize == 40) {
biWidth = SDL_ReadLE32(src);
biHeight = SDL_ReadLE32(src);
biPlanes = SDL_ReadLE16(src);
biBitCount = SDL_ReadLE16(src);
biCompression = SDL_ReadLE32(src);
biSizeImage = SDL_ReadLE32(src);
biXPelsPerMeter = SDL_ReadLE32(src);
biYPelsPerMeter = SDL_ReadLE32(src);
biClrUsed = SDL_ReadLE32(src);
biClrImportant = SDL_ReadLE32(src);
} else {
SDL_SetError("Unsupported ICO bitmap format");
621
was_error = SDL_TRUE;
622
623
624
625
626
goto done;
}
/* Check for read error */
if (SDL_strcmp(SDL_GetError(), "") != 0) {
627
was_error = SDL_TRUE;
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
goto done;
}
/* We don't support any BMP compression right now */
switch (biCompression) {
case BI_RGB:
/* Default values for the BMP format */
switch (biBitCount) {
case 1:
case 4:
ExpandBMP = biBitCount;
biBitCount = 8;
break;
case 8:
ExpandBMP = 8;
break;
case 32:
Rmask = 0x00FF0000;
Gmask = 0x0000FF00;
Bmask = 0x000000FF;
ExpandBMP = 0;
break;
default:
SDL_SetError("ICO file with unsupported bit count");
652
was_error = SDL_TRUE;
653
654
655
656
657
goto done;
}
break;
default:
SDL_SetError("Compressed ICO files not supported");
658
was_error = SDL_TRUE;
659
660
661
662
663
664
665
666
667
668
goto done;
}
/* Create a RGBA surface */
biHeight = biHeight >> 1;
//printf("%d x %d\n", biWidth, biHeight);
surface =
SDL_CreateRGBSurface(0, biWidth, biHeight, 32, 0x00FF0000,
0x0000FF00, 0x000000FF, 0xFF000000);
if (surface == NULL) {
669
was_error = SDL_TRUE;
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
goto done;
}
/* Load the palette, if any */
//printf("bc %d bused %d\n", biBitCount, biClrUsed);
if (biBitCount <= 8) {
if (biClrUsed == 0) {
biClrUsed = 1 << biBitCount;
}
for (i = 0; i < (int) biClrUsed; ++i) {
SDL_RWread(src, &palette[i], 4, 1);
}
}
/* Read the surface pixels. Note that the bmp image is upside down */
bits = (Uint8 *) surface->pixels + (surface->h * surface->pitch);
switch (ExpandBMP) {
case 1:
bmpPitch = (biWidth + 7) >> 3;
pad = (((bmpPitch) % 4) ? (4 - ((bmpPitch) % 4)) : 0);
break;
case 4:
bmpPitch = (biWidth + 1) >> 1;
pad = (((bmpPitch) % 4) ? (4 - ((bmpPitch) % 4)) : 0);
break;
case 8:
bmpPitch = biWidth;
pad = (((bmpPitch) % 4) ? (4 - ((bmpPitch) % 4)) : 0);
break;
default:
bmpPitch = biWidth * 4;
pad = 0;
break;
}
while (bits > (Uint8 *) surface->pixels) {
bits -= surface->pitch;
switch (ExpandBMP) {
case 1:
case 4:
case 8:
{
Uint8 pixel = 0;
int shift = (8 - ExpandBMP);
for (i = 0; i < surface->w; ++i) {
if (i % (8 / ExpandBMP) == 0) {
if (!SDL_RWread(src, &pixel, 1, 1)) {
SDL_SetError("Error reading from ICO");
717
was_error = SDL_TRUE;
718
719
720
721
722
723
724
725
726
727
728
729
730
goto done;
}
}
*((Uint32 *) bits + i) = (palette[pixel >> shift]);
pixel <<= ExpandBMP;
}
}
break;
default:
if (SDL_RWread(src, bits, 1, surface->pitch)
!= surface->pitch) {
SDL_Error(SDL_EFREAD);
731
was_error = SDL_TRUE;
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
goto done;
}
break;
}
/* Skip padding bytes, ugh */
if (pad) {
Uint8 padbyte;
for (i = 0; i < pad; ++i) {
SDL_RWread(src, &padbyte, 1, 1);
}
}
}
/* Read the mask pixels. Note that the bmp image is upside down */
bits = (Uint8 *) surface->pixels + (surface->h * surface->pitch);
ExpandBMP = 1;
bmpPitch = (biWidth + 7) >> 3;
pad = (((bmpPitch) % 4) ? (4 - ((bmpPitch) % 4)) : 0);
while (bits > (Uint8 *) surface->pixels) {
Uint8 pixel = 0;
int shift = (8 - ExpandBMP);
bits -= surface->pitch;
for (i = 0; i < surface->w; ++i) {
if (i % (8 / ExpandBMP) == 0) {
if (!SDL_RWread(src, &pixel, 1, 1)) {
SDL_SetError("Error reading from ICO");
758
was_error = SDL_TRUE;
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
goto done;
}
}
*((Uint32 *) bits + i) |= ((pixel >> shift) ? 0 : 0xFF000000);
pixel <<= ExpandBMP;
}
/* Skip padding bytes, ugh */
if (pad) {
Uint8 padbyte;
for (i = 0; i < pad; ++i) {
SDL_RWread(src, &padbyte, 1, 1);
}
}
}
done:
if (was_error) {
if (src) {
SDL_RWseek(src, fp_offset, RW_SEEK_SET);
}
if (surface) {
SDL_FreeSurface(surface);
}
surface = NULL;
}
if (freesrc && src) {
SDL_RWclose(src);
}
return (surface);
}
789
790
791
/* Load a BMP type image from an SDL datasource */
SDL_Surface *IMG_LoadBMP_RW(SDL_RWops *src)
{
792
return(LoadBMP_RW(src, 0));
793
794
}
795
796
797
798
799
800
801
802
803
804
805
806
/* Load a ICO type image from an SDL datasource */
SDL_Surface *IMG_LoadICO_RW(SDL_RWops *src)
{
return(LoadICOCUR_RW(src, 1, 0));
}
/* Load a CUR type image from an SDL datasource */
SDL_Surface *IMG_LoadCUR_RW(SDL_RWops *src)
{
return(LoadICOCUR_RW(src, 2, 0));
}
807
808
809
810
811
812
813
814
#else
/* See if an image is contained in a data source */
int IMG_isBMP(SDL_RWops *src)
{
return(0);
}
815
816
817
818
819
820
821
822
823
824
int IMG_isICO(SDL_RWops *src)
{
return(0);
}
int IMG_isCUR(SDL_RWops *src)
{
return(0);
}
825
826
827
828
829
830
/* Load a BMP type image from an SDL datasource */
SDL_Surface *IMG_LoadBMP_RW(SDL_RWops *src)
{
return(NULL);
}
831
832
833
834
835
836
837
838
839
840
841
842
/* Load a BMP type image from an SDL datasource */
SDL_Surface *IMG_LoadCUR_RW(SDL_RWops *src)
{
return(NULL);
}
/* Load a BMP type image from an SDL datasource */
SDL_Surface *IMG_LoadICO_RW(SDL_RWops *src)
{
return(NULL);
}
843
#endif /* LOAD_BMP */
844
845
#endif /* !defined(__APPLE__) || defined(SDL_IMAGE_USE_COMMON_BACKEND) */